Cheapest priced copy (Murders at Karlov Manor Commander): $0.99 at Card Kingdom, near mint, their price list as of .
Tezzeret, Betrayer of Flesh 
Legendary Planeswalker — Tezzeret · Mythic · Kamigawa: Neon Dynasty · #84
The first activated ability of an artifact you activate each turn costs {2} less to activate.
+1: Draw two cards. Then discard two cards unless you discard an artifact card.
−2: Target artifact becomes an artifact creature. If it isn't a Vehicle, it has base power and toughness 4/4.
−6: You get an emblem with "Whenever an artifact you control becomes tapped, draw a card."
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
7 printings · $0.99 to $5.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Murders at Karlov Manor Commander | 120 | Mythic | $0.99 | — |
| Kamigawa: Neon Dynasty | 84 | Mythic | $0.99 | $0.99 |
| Kamigawa: Neon Dynasty | 304 | Mythic | $4.49 | $5.99 |
| Kamigawa: Neon Dynasty | 376 | Mythic | $2.99 | $3.49 |
| Kamigawa: Neon Dynasty | 419 | Mythic | — | — |
| Kamigawa: Neon Dynasty Promos | 84p | Mythic | $5.99 | $5.99 |
| Kamigawa: Neon Dynasty Promos | 84s | Mythic | — | $2.29 |
4 rulings from Wizards of the Coast
- 18 February 2022If you begin to activate an ability that costs mana before activating any mana abilities you need to pay for it, that ability will be the one to get Tezzeret's discount. The total cost for that ability becomes locked in, and then you can activate mana abilities to pay for it.
- 18 February 2022If Tezzeret's second loyalty ability causes a Vehicle to become an artifact creature, it doesn't count as "crewing" that Vehicle for any ability that would trigger off of a Vehicle becoming crewed.
- 18 February 2022If you activate Tezzeret's second loyalty ability targeting a Vehicle, it will have its printed power and toughness.
- 18 February 2022Tezzeret, Betrayer of Flesh's first ability reduces the cost of the first activated ability of an artifact that you begin to activate each turn. The second ability (and any subsequent abilities) of an artifact you activate that turn won't cost {2} less to activate, even if the first ability you activated didn't cost any mana to begin with. Notably, this does not exclude mana abilities.